Plastic is the primary material used for the production of a wide variety of consumer goods due to its technical and structural characteristics, which allow for the development of solutions that are stronger, lighter, and more versatile, but above all, at lower costs.
However, even today, many manufacturing processes involve the use of metallic materials instead of plastic, justifying their use with a presumed greater resistance to atmospheric elements or physical stress, but is this really the case?
We know that, since their invention, plastics have contributed to increasingly massive innovation in other industrial sectors, immediately proving to be more malleable and versatile than most natural raw materials precisely because of the intrinsic characteristics of plastic.
Over time, thanks to the development of new catalysts and the synthesis of new engineering polymers, the plastics industry has played an increasingly central role in the global production of manufactured goods, so much so that we can finally begin to speak of a “plastic transition” or “metal replacement,” as metal is effectively the ultimate material that is most difficult to replace with equivalent solutions.
Nevertheless, although part of the industry is still not confident in the advantages deriving from “metal replacement,” we are facing a period of epochal change, driven by the numerous benefits strictly linked to the use of high-performance polymers instead of heavier and more expensive materials, the use of which is slowly losing justification thanks to the excellent performance and economic savings associated with new plastic materials.
In fact, making a metal part out of plastic is no longer exclusively a matter of reducing the weight of the product, as the most modern engineered plastics are able to compete with metal from multiple points of view, effectively making material replacement a true long-term investment.
But specifically, what are the desirable characteristics that make high-potential polymers such a valid substitute?
- Firstly, it is essential to highlight the significant savings in terms of both costs and resources resulting from the use of plastic. In fact, thanks to the injection molding process, material usage is optimized and industrial cycle times are accelerated, as the production of parts does not require any secondary processing aimed at making products identical, consequently reducing waste production.
- Secondly, the malleable nature of polymers allows for intervention during the injection molding process to perform a series of more structured treatments on the material, such as coloring, layering, or polishing, thereby eliminating all those secondary operations that complicate the production process. In doing so, the production and assembly process of complex pieces, composed of several metal parts fused or fixed together by welding, can also be simplified by creating a single injection-molded plastic element and bypassing the need for welded joints between parts, consequently preventing potential leaks.
- The use of top-quality engineered plastic materials allows for very high levels of resistance to physical stress, almost comparable to those of many metal alloys. Furthermore, during the injection molding process, it is possible to arrange specific design solutions that increase structural strength without significantly impacting the cost of the part.
- A natural consequence of using plastic instead of metal is the reduction in the overall weight of the product, a sensitive factor both for the needs of the end user and for the reduction of shipping and assembly costs.
- Due to their engineered nature, individual parts made of high-potential polymers can be designed to better resist atmospheric agents. Furthermore, thanks to the greater chemical resistance typical of the material, it is not affected by corrosive factors that can attack metal, such as rust or oxidation.
- Finally, the use of plastic materials allows for the optimization of the production process by recovering and reusing waste parts more simply and immediately than would be possible with metal production waste, which can indeed be remelted, but with longer timeframes and more complex methods. Thermoplastic residues can be easily ground into their original form, namely pellets, and reintroduced into the industrial cycle without particular difficulty or additional costs.
We have seen that plastic materials, and specifically engineering polymers, perform at their best when the production chain is redesigned for plastic, innovating production processes and reconfiguring the approach during the design phase.
At the current rate of replacement, it has been estimated that in the near future, 25% of a car’s weight will consist of plastic components, demonstrating the advantages linked to the more massive implementation of this material in production processes.
It is precisely in this direction that the plastics industry is moving, as demonstrated by the main topic of the Smart Plastic 2021 conference, focused on Engineering Polymers, in which Rifra had the opportunity to participate by presenting its line of color Masterbatches, Rifra Ultratech, capable of guaranteeing maximum performance even at temperatures exceeding 300°C.
In conclusion, there is no doubt that thanks to the development of high-performance polymers, the era of metal replacement has just begun.
Certainly, not everything currently made of metal can be replaced with synthetic polymer materials; however, the advantages deriving from the implementation of plastic products instead of their metal counterparts are evident both from the point of view of timing and costs, and from the point of view of environmental impact, helping our society move towards a greener and more sustainable future.
